.back_head {
    width: 80%;
    padding: 0 10%;
}

.back_header_left {
    float: left;
    height: 80px;
    width: 40%;
}

.back_header_right {
    float: right;
    width: 40%;
    line-height: 20px;
    text-align: right;
}

.back_current_user {
    text-decoration: underline;
}

.back_exit {
    color: red;
    cursor: pointer;
    text-decoration: none;
}

#back_curent_time {
    height: 25px;
    line-height: 25px;
}

.p-style {
    height: 40px;
}